Method and system for obtaining emergency caller location

ABSTRACT

Methods and systems for obtaining the location of a caller during an emergency or other telephone call. Before or during a call, a phone system can obtain from one or more sources a subscriber access line identity associated with a subscriber location record that includes a subscriber access line identity attribute and a subscriber location attribute. A phone system can send a query that includes the subscriber access line identity to a subscriber location query system that returns a subscriber location record or a subscriber location to the phone system. The phone system can then display the caller location information to a phone system, an agent or operator so that emergency services can be quickly and accurately dispatched. Using similar procedure and a memory, phone systems can also determine if a subscriber phone has or is changing location. Methods for testing the emergency call capabilities of a subscriber access line.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application entitled“Method and System for Obtaining Emergency Caller Location”, Ser. No.11/182,219, filed on Jul. 14, 2005 now U.S. Pat. No. 7,272,402.

BACKGROUND

1. Field

This invention relates generally to telecommunications, morespecifically, to a method and system to provide location information forvoice calls.

2. Related Art

Around the world there are many emergency telephone numbers. Forexample, in the United States of America, the three-digit telephonenumber “911” is designated as the universal emergency telephone number.In the case of an emergency, a person can call 911 to reach an operatorwho can dispatch appropriate emergency services. To help provide thetimeliest response, it is helpful and often necessary to have thelocation of the caller reported to the emergency service dispatcher.This is feature is of utmost importance when the caller is a youngchild, someone who is very ill or injured or otherwise unable toeffectively communicate their location to the emergency servicesdispatcher. For these services to function properly, the telephoneservice provider must have means of identifying and reporting thelocation of the emergency caller.

In a typical scenario, when a subscriber subscribes to a residentialtelephone service from a service provider, the service provider assignsa telephone number for that subscription and allocates an access line tothe subscriber's residence for the service. The access line connects toa telephone system of the residential telephone service. A user connectsa telephone to the access line and uses the telephone to receive theresidential telephone service.

The location of the subscription is the connecting point of the accessline and the telephone. The location is typically the street address ofthe subscriber's residence. The service provider submits the telephonenumber and the location of the subscription to create a record in anAutomatic Location identity (ALI) database. The record maps thetelephone number to the location of the subscription. One of the usagesof ALI database is for Emergency call purpose.

When a caller uses the telephone to make an emergency call by dialing“911”, the telephone system determines the telephone number associatedwith the subscription. The telephone system sends a call request to a911 selective router telephone system. The call request includes thetelephone number.

The 911-selective router telephone system receives the telephone numberin the call request and retrieves from the ALI database the location ofthe subscription based on the telephone number. The location ispresumably where the caller of the emergency call is. The 911-selectiverouter telephone system uses the location to select a Public SafetyAnswering Point (PSAP), which is a telephone system. The 911-selectiverouter telephone system further sends the emergency call request to thePSAP. The call request also includes the telephone number.

The PSAP presents the emergency call to an emergency call agent. ThePSAP also retrieves from the ALI database the location of thesubscription based on the telephone number in the emergency callrequest, and informs the emergency call agent of the location from whichthe call originated. The agent uses the location to dispatch emergencypersonnel and services.

Recently, various service providers have been rolling out new telephoneservices. These telephone services include cellular telephone services,and Voice over IP (VoIP) telephone services. Although these telephoneservices are not the same as traditional residential telephone services,they are either marketed as residential telephone services orsubscribers use them as if they are equivalent to residential telephoneservices. Many consumers mistakenly assume that 911 or emergencyservices will be available in these new telephone services as they arein traditional residential telephone services. However this is often notthe case. Cellular and VoIP telephone services, due to their ability tomove from one physical location to another, present a fairly complexproblem when it come to providing emergency call services. Especiallywhen those services are highly dependent on knowing from whence theemergency call is being made.

In the case of VoIP telephone service, a user receives VoIP telephoneservice by connecting an IP telephone to a VoIP telephone system via theInternet. In one scenario, the IP telephone may be connected to a homeDSL broadband Internet access gateway. It is also possible to connectthe same IP telephone to a neighbor's Cable Modem broadband Internetaccess gateway. As a further convenience, is it also possible to connectan IP telephone to the IP network of a hotel during an out-of-town trip.In each example, the IP telephone is used to receive VoIP telephoneservice. While the convenience of being able to travel to any locationwith an appropriate Internet access, there is a danger associated withassuming that emergency services will be available on the IP telephoneas on a regular telephone. To illustrate this danger, consider thefollowing scenario.

While out of town, a user has an accident or encounters an emergency.The user calls 911 on an IP telephone that they have brought from home.The user assumes the 911-emergency call center would know her location,and expects emergency services to arrive in a short period of time. Whenthe emergency call is not answered or when emergency services do notarrive in an hour, the user panics. Whilst in the hotel, the user'sspouse calls the user's IP telephone number from their home concernedthat emergency services were dispatched to their home for her whilst sheis away. From the IP telephone service, the emergency dispatch serviceshad no way of knowing her location.

As shown in the new telephone services, there is a need for afundamentally new solution to provide the correct location of a callerduring an emergency call.

SUMMARY

Embodiments of the present include systems and methods for obtaining thelocation of a caller during a telephone call.

In one embodiment, a phone system obtains the subscriber access lineidentity of a subscriber access line and sends it to a subscriberlocation query system which then returns a subscriber location or asubscriber location record.

In another embodiment, subscriber phone equipment or phone can store asubscriber access line identity. The subscriber line identity stored inthe subscriber phone equipment or phone can be used to retrieve thesubscriber location record with the corresponding subscriber access lineidentity stored its subscriber access line identity attribute and aknown location stored in its subscriber location attribute to compare tosubscriber access line identities obtained during calls to determine ifthe subscriber phone equipment has changed location.

In yet another embodiment, the emergency call capabilities of asubscriber access line are determined by an emergency call test modulesending out a test signal or query to a subscriber access line module, aphone system or subscriber access line.

Additional embodiments will be evident from the following detaileddescription and accompanying drawings, which provide a betterunderstanding of the nature and advantages of the present invention

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating the connections betweensubscriber access line module and subscriber phone equipment through asubscriber access line.

FIG. 2 is a block diagram illustrating a subscriber location record.

FIG. 3 is a block diagram illustrating the connections between asubscriber location datastore and a subscriber location query system.

FIG. 4 is a block diagram illustrating a system for obtaining asubscriber location during a call.

FIG. 5 is a block diagram illustrating a system for handling anemergency call.

FIG. 6 is a block diagram illustrating a method of testing whether ornot an emergency call can be made using a subscriber access line.

FIG. 7 is a block diagram illustrating a system for determining whetheror not subscriber phone equipment has changed location.

DETAILED DESCRIPTION Subscriber Phone Equipment, Subscriber Access Line,and Subscriber Access Line Module

FIG. 1 illustrates a subscriber access line module 130 connection tosubscriber phone equipment 110. Subscriber phone equipment 110 connectsto subscriber access line module 130 via a subscriber access line 135.Subscriber access line module 130 can connect to multiple subscriberphone equipment simultaneously through multiple subscriber access lines.Each subscriber access line 135 has a subscriber access line identity.Each subscriber access line 135 has a subscriber location. Thesubscriber location of a subscriber access line 135 is the locationwhere the subscriber access line 135 connects to subscriber phoneequipment 110. In one embodiment, a subscriber location includes astreet address. In another embodiment, a subscriber location includes abuilding number. In yet another embodiment, a subscriber locationincludes a room number. In one embodiment, a subscriber locationincludes a cubicle number. In a different embodiment, a subscriberlocation includes a geophysical location.

Subscriber access line module 130 manages the association between asubscriber access line 135 and the subscriber access line identity thatidentifies the subscriber access line 135. In one embodiment, subscriberaccess line module 130 includes a Master Distribution Frame (MDF). Inanother embodiment, subscriber access line module 130 includes a DigitalSubscriber Line Access Multiplexer (DSLAM). In yet another embodiment,subscriber access line module 130 includes a Digital Loop Carrier (DLC).In a different embodiment, subscriber access line module 130 includesCable Headend equipment, such as a Cable Modem Termination System (CMTS)or a Cable Data Modem Termination System (CDMTS). In another embodiment,subscriber access line module 130 includes radio network accessequipment, such as base stations and base station controllers (BSC).

In one embodiment, subscriber access line 135 includes a copper localloop. In another embodiment, subscriber access line 135 includes acoaxial cable. In another embodiment, subscriber access line 135includes a radio frequency band. In one embodiment, subscriber accessline 135 includes a multiplex channel within the radio frequency band.In another embodiment, the multiplex channel is based on Time DivisionMultiplexing Access (TDMA) technology. In another embodiment, themultiplex channel is based on Code Division Multiplexing Access (CDMA)technology. In yet another embodiment, the multiplex channel is based onFrequency Division Multiplexing Access (FDMA) technology.

Subscriber Location Record and Subscriber Location Datastore

FIG. 2 illustrates a subscriber location record. A subscriber locationrecord 280 comprises a subscriber access line identity attribute 285 anda subscriber location attribute 287. In one embodiment, subscriberaccess line identity attribute 285 includes the subscriber access lineidentity of a subscriber access line. In one embodiment, subscriberlocation attribute 287 includes the subscriber location of thesubscriber access line. The location stored in the subscriber locationattribute can be a physical address such as a street address, a buildingnumber, a cubicle number, or geophysical location coordinates.

Subscriber Location Datastore and Subscriber Location Query System

FIG. 3 illustrates a process for querying a subscriber location.Subscriber location datastore 370 connects to a subscriber locationquery system 380. Subscriber location datastore 370 includes a pluralityof subscriber location records. Subscriber location query system 380receives a query for a subscriber location. The query includes asubscriber access line identity 312. In one embodiment, subscriberlocation query system 380 compares the subscriber access line identitywith the subscriber access line identity attribute of multiplesubscriber location records in subscriber location datastore 370. If amatching subscriber location record exists, subscriber location querysystem 380 selects one or more of the matching subscriber locationrecord 316.

Subscriber location query system 380 sends the result 318 in response tothe query. In one embodiment, the result 318 is the subscriber locationextracted from the subscriber location attribute of the selectedsubscriber location record 316. In another embodiment, the result is oneor more of the selected subscriber location record 316.

In one embodiment, subscriber location query system 380 receives thequery from a network. In one embodiment, the network is a SignalingSystem 7 (SS7) network. In another embodiment, the network is anInternet Protocol (IP) network. In yet another embodiment, subscriberlocation query system 380 receives the query over a circuitryconnection. In a different embodiment, subscriber location query system380 receives the query over an Application Programming Interface (API).In a one embodiment, subscriber location query system 380 receives thequery via a standard base database access protocol. In anotherembodiment, subscriber location query system 380 receives the query viaa proprietary protocol.

A Method of Obtaining Subscriber Location During a Call

FIG. 4 illustrates a system for obtaining a subscriber location during acall.

Subscriber phone equipment 410 connects to a subscriber access linemodule 430 over a subscriber access line 435. A phone 417 connects tosubscriber access line module 430 over the subscriber access line 435.Subscriber access line module 430 connects to a phone system 490. A useruses phone 417 to make a call.

Phone system 490 receives and processes the call from phone 417. Phonesystem 490 determines the subscriber access line identity of thesubscriber access line as to where phone 417 is connected.

In one embodiment, phone system 490 determines the subscriber accessline identity by correlating the resources in phone system 490. In oneembodiment, the resources include a line card and a port. In anotherembodiment, the resources include a multiplexing channel in thecommunications media between phone system 490 and subscriber access linemodule 430.

In another embodiment, phone system 490 determines the subscriber accessline identity by querying subscriber access line module 430. In oneembodiment, phone system 490 queries subscriber access line module 430during processing of the call. In another embodiment, phone system 490queries subscriber access line module 430 before the call.

In another embodiment, phone system 490 connects to subscriber phoneequipment 410. Subscriber phone equipment 410 obtains the subscriberaccess line identity of subscriber access line 435 from subscriberaccess line module 430. Phone system 490 determines the subscriberaccess line identity by querying subscriber phone equipment 410. In oneembodiment, phone system 490 queries subscriber phone equipment 410during processing of the call. In another embodiment, phone system 490queries subscriber phone equipment 410 before the call.

In yet another embodiment, phone 417 stores, includes or otherwise hasthe subscriber access line identity of subscriber access line 435. Phonesystem 490 determines the subscriber access line identity from phone417. In one embodiment, phone system 490 determines the subscriberaccess line identity from phone 417 during processing of the call. Inanother embodiment, phone system 490 determines the subscriber accessline identity from phone 417 before the call.

In FIG. 4, phone system 490 connects to a subscriber location querysystem 480. Phone system 490 sends a query to subscriber location querysystem 480. The query includes the determined subscriber access lineidentity. Phone system 490 receives a subscriber location fromsubscriber location query system 480.

In one embodiment, phone system 490 connects to another phone system495. Phone system 490 sends a call request to phone system 495. In oneembodiment, phone system 490 includes the determined subscriber accessline identity in the call request. phone system 495 receives thedetermined subscriber access line identity from phone system 490. Phonesystem 495 determines the subscriber location from the receivedsubscriber access line identity by querying subscriber location querysystem 480.

A Method of Obtaining the Location of a Caller During an Emergency Call.

FIG. 5 illustrates a method of handling an emergency call. Phone system590 connects to an emergency response phone system 595. Emergencyresponse phone system 595 comprises one or more phone systems. Emergencyresponse phone system 595 connects to subscriber location query system580. Subscriber phone equipment 510 connects to a subscriber access linemodule 530 over a subscriber access line 535. phone 517 connects tosubscriber access line module 530 over the subscriber access line 535.Subscriber access line module 530 connects to phone system 590.

A user makes an emergency call by dialing an emergency number at phone517.

In one embodiment, the emergency number is “Emergency”. In anotherembodiment, the emergency number is “999”. In yet another embodiment,the emergency number is “911”. Phone system 590 receives the emergencycall, and determines the subscriber access line identity of subscriberaccess line 535 as illustrated in FIG. 4.

Phone system 590 routes the emergency call to emergency response phonesystem 595 and sends the determined subscriber access line identity toemergency response phone system 595.

Emergency response phone system 595 receives the emergency call and thesubscriber access line identity. Emergency response phone system 595determines the subscriber location by querying the subscriber locationquery system 580 using the received subscriber access line identity.Emergency response phone system 595 presents the emergency call,including the subscriber location, to an agent. The agent dispatchesemergency personnel to subscriber location. In one embodiment, the agentdispatches emergency personnel to the street address indicated in thesubscriber location. In an embodiment, the agent dispatches emergencypersonnel to the cubical of a building indicated in the subscriberlocation. In a different embodiment, the agent dispatches emergencypersonnel to search in the geophysical location indicated in thesubscriber location.

A Method of Obtaining if an Emergency Call can be Made Using aSubscriber Access Line

FIG. 6 illustrates a method of obtaining if an emergency call can bemade using a subscriber access line. Subscriber phone equipment 610includes an emergency call test module 615. Subscriber phone equipment610 connects to subscriber access line module 630 over subscriber accessline 635. Subscriber access line module 630 connects to a phone system690. Emergency call test module 615 performs a test to determine if anemergency call can be made using the subscriber access line 635.

In one embodiment, emergency call test module 615 queries subscriberaccess line module 630. Subscriber access line module 630 responds withan indication whether or not an emergency call can be made. Emergencycall test module 615 checks the indication. If the indication ispositive, emergency call test module 615 determines that an emergencycall can be made using the subscriber access line 635.

In another embodiment, subscriber phone equipment 630 connects to phonesystem 690. Emergency call test module 615 queries phone system 690.Phone system 690 responds with an indication whether or not an emergencycall can be made. Emergency call test module 615 checks the indication.If the indication is positive, emergency call test module 615 determinesthat an emergency call can be made using the subscriber access line 635.

In one embodiment, emergency call test module 615 sends an off hooksignal towards subscriber access line 635, and checks for an indicationof a dial tone. If the indication is positive, emergency call testmodule 615 determines that an emergency call can be made using thesubscriber access line 635.

In one embodiment, emergency call test module 615 repeats the process amultiple times before determining if an emergency call can be made usingthe subscriber access line 635.

In one embodiment, subscriber phone equipment 610 connects to atelephone. Subscriber phone equipment 610 informs the telephone if anemergency call can be made using the subscriber access line 635.

In one embodiment, subscriber phone equipment 610 further includes anemergency call test indicator 613. Emergency call test module 615connects to an emergency call test indicator 613. In one embodiment,emergency call test indicator 613 includes a visual indicator such as alight or display.

In one embodiment, emergency call test indicator 613 includes a LED asthe visual indicator. If emergency call test module 615 determines thatan emergency call can be made using the subscriber access line 635,emergency call test module 615 turns the LED or other visual indicatorto green. In one embodiment, if emergency call test module 615 cannotdetermine an emergency call can be made using the subscriber access line635, emergency call test module 615 turns the LED to red.

In another embodiment, emergency call test indicator 613 includes a textdisplay panel. If emergency call test module 615 determines an emergencycall can be made using the subscriber access line 635, emergency calltest module 615 displays “emergency call Test Succeeds” on the displaypanel. In one embodiment, emergency call test module 615 cannotdetermine that an emergency call can be made using the subscriber accessline 635 emergency call test module 615 displays “emergency call Testfails” on the display panel.

In one embodiment, emergency call test module 615 determines repeatedlyif an emergency call can be made using the subscriber access line 635.In one embodiment, emergency call test module 615 performs the processevery 30 minutes. In another embodiment, emergency call test module 615performs the process every hour. In yet another embodiment, emergencycall test module 615 performs the process when subscriber phoneequipment 610 powers up. In a different embodiment, emergency call testmodule 615 performs the process when a telephone call is made.

A Method of Determining Whether or not Subscriber Phone Equipment hasChanged Location

FIG. 7 illustrates a process to determine whether or not subscriberphone equipment has changed location. Subscriber phone equipment 710includes a location test module 715.

A Method of Determining Whether or not Subscriber Phone Equipment hasChanged Location Based on Subscriber Access Line Identity

In one embodiment, location test module 715 determines whether or notsubscriber phone equipment 710 has changed location by examining thesubscriber access line identity of subscriber access line 735.Subscriber phone equipment 710 connects to subscriber access line module730 over subscriber access line 735. Subscriber access line module 730connects to a phone system 790.

In one embodiment, location test module 715 connects to datastore 719.Datastore 719 stores a stored subscriber access line identity 718. Thestored subscriber access line identity 718 is a subscriber access lineidentity identifying a subscriber access line with subscriber locationbeing the correct location of the subscriber phone equipment 710. In oneembodiment, datastore 719 is a flash memory. In another embodiment,datastore is a hard disk. In yet another embodiment, datastore 719 is amemory.

Location test module 715 obtains the stored subscriber access lineidentity 718 and stores the stored subscriber access line identity 718in datastore 719. In one embodiment, the stored subscriber access lineidentity 718 is determined when the service provider establishes aservice for the subscriber. In one embodiment, during serviceestablishment, the service provider informs the location test module 715of the stored subscriber access line identity 718. In anotherembodiment, location test module 715 obtains from subscriber access linemodule 730 the stored subscriber access line identity 718. In anotherembodiment, stored subscriber access line identity 718 is determinedduring a service change. In another scenario, the subscriber movessubscriber phone equipment 710 to a new location, and submits a newaddress to the service provider. The service provider determines a newstored subscriber access line identity 718. In another embodiment, theservice provider informs the location test module 715 of the new storedsubscriber access line identity 718. In yet another embodiment, locationtest module 715 obtains from subscriber access line module 730 the newstored subscriber access line identity 718.

In one embodiment, location test module 715 connects to a phone system790. Location test module 715 obtains the stored subscriber lineidentity 718 from phone system 790.

In one embodiment, location test module 715 connects to a phone 717.Location test module 715 obtains stored subscriber access line identity718 from phone 717.

In one embodiment, location test module 715 is informed when a newstored subscriber line identity 718 is available. In another embodiment,location test module 715 checks for a new stored subscriber lineidentity 718. In an embodiment, location test module 715 checks every 5minutes. In a different embodiment, location test module 715 checksevery hour.

Location test module 715 determines whether or not subscriber phoneequipment 710 has changed location by matching the stored subscriberaccess line identity 718 against the subscriber access line identity ofsubscriber access line 735. If the match succeeds, location test module715 concludes that subscriber phone equipment 710 has not changedlocation.

In one embodiment, location test module 715 obtains the subscriberaccess line identity of subscriber access line 735 from subscriberaccess line module 730. In another embodiment, location test module 715obtains the subscriber access line identity of subscriber access line735 from phone system 790. In yet a different embodiment, location testmodule 715 obtains the subscriber access line identity of subscriberaccess line 735 from phone 717.

A Method of Determining Whether or not Subscriber Phone Equipment hasChanged Location in Voice Over IP (VoIP) Phone Services

In one embodiment, phone 717 connects to phone system 790 based on VoIPservice. Phone 717 has an IP address. Phone 717 has an IP address asseen by phone system 790.

In one embodiment, location test module 715 sends a message to phone717. In one embodiment, phone 717 responds with an indication aboutwhether or not the IP address of phone 717 has changed. In anotherembodiment, phone 717 responds with an indication about whether or notthe IP address of phone 717 as seen by phone system 790 has changed.Location test module 715 can determine based on the indication receivedfrom phone 717 whether or not subscriber phone equipment 710 has changedlocation.

In one embodiment, location test module 715 sends a message to phonesystem 790. In one embodiment, phone system 790 responds with anindication about whether or not the IP address of phone 717 has changed.In another embodiment, phone system 790 responds with an indicationabout whether or not the IP address of phone 717 as seen by phone system790 has changed. Location test module 715 can determine based on theindication received from phone 717 whether or not subscriber phoneequipment 710 has changed location.

In one embodiment, location test module 715 sends a message to phone 717and a message to phone system 790. Location test module 715 concludesthat subscriber phone equipment 710 has not changed location if phone717 responds that the IP address of phone 717 has not changed and phonesystem 790 responds that the IP address of phone 717 as seen by phonesystem 790 has not changed.

In another embodiment, location test module 715 tests whether or notsubscriber phone equipment 710 has changed location every 30 minutes. Inanother embodiment, location test module 715 tests whether or notsubscriber phone equipment 710 has changed location every hour. In yetanother embodiment, location test module 715 tests whether or notsubscriber phone equipment 710 has changed location when subscriberphone equipment 710 powers up. In a different embodiment, location testmodule 715 tests whether or not subscriber phone equipment 710 haschanged location when a user makes a telephone call.

In one embodiment, subscriber phone equipment 710 connects to phone 717.Subscriber phone equipment 710 informs phone 717 whether or notsubscriber phone equipment 710 has changed location. In one embodiment,subscriber phone equipment 710 further includes a location testindicator 713. Location test module 715 connects to the location testindicator 713.

In according to one embodiment, location test indicator 713 includes avisual indicator such as a light or a display. In one embodiment, thevisual indicator is an LED. If location test module 715 determines thatsubscriber phone equipment 710 has not changed location, location testmodule 715 turns the LED to green. In one embodiment, if location testmodule 715 cannot determine that subscriber phone equipment 710 has notchanged location, location test module 715 turns the LED to red. Inanother embodiment, the visual indicator is a display panel. If locationtest module 715 determines that subscriber phone equipment 710 has notchanged location, location test module 717 displays “Location correct”on the display panel. If location test module 715 cannot determine thatsubscriber phone equipment 710 has not changed location, location Testmodule 717 displays “Location may be incorrect” on the display panel.

Combining Emergency Call Test and Location Test

In one embodiment, subscriber phone equipment includes an emergency calltest module and a location test module. Subscriber phone equipment canperform both tests provided for by the emergency call test module andthe location test module. In one embodiment, subscriber phone equipmentfurther connects to a test indicator. The test indicator can include avisual indicator such as a light or a display.

In one embodiment, emergency call test module determines whether or notan emergency call can be made and location test module determineswhether or not subscriber phone equipment has changed location. In oneembodiment, emergency call test module determines that an emergency callcan be made and determines that subscriber phone equipment has notchanged locations; then subscriber phone equipment turns the visualindicator, such as an LED, to green. In another embodiment, emergencycall test module determines that an emergency call can be made andlocation test module cannot determine whether or not subscriber phoneequipment has changed location; then subscriber phone equipment turnsthe visual indicator, such as an LED, to yellow. In yet anotherembodiment, emergency call test module cannot determine that anemergency call can be made and location test module determines thatsubscriber phone equipment has not changed location; subscriber phoneequipment turns the LED to amber. In one other embodiment, emergencycall test module cannot determine that an emergency call can be made andlocation test module cannot determine that subscriber phone equipmenthas not changed location; subscriber phone equipment turns the LED tored.

In a different embodiment, the test indicator visual indicator is adisplay panel. Subscriber phone equipment displays correspondingmessages on the display panel based on the combined test results ofemergency call test module and location test module.

Subscriber Location Changes During an Emergency Call

While a user is making an emergency call, the user may move from alocation to another location. The phone system handling the call candiscover, from time to time, the subscriber access line identity of thesubscriber access line to which the phone is connected. In oneembodiment, after obtaining a subscriber access line identity, the phonesystem sends the subscriber access line identity to the emergencyresponse phone system. In another embodiment, the phone system detects achange in subscriber access line identity, and sends the new subscriberaccess line identity to the emergency response phone system. Theemergency response phone system further presents to the agent with anupdated subscriber location.

A Method of Selecting a Phone System while Making Emergency Calls in aVoIP Service Scenario

In FIG. 5, when a phone 517 makes an emergency call, phone 517 routesthe emergency call to a phone system 590. In one embodiment, thetelephone service is a VoIP service. The VoIP service provider istypically not the service provider for the subscriber access line 535.In one embodiment, the subscriber access line service provider offerstelephone services and has a plurality of phone system from thesubscriber access line service provider. When a user makes an emergencycall, the user can select a phone system from the subscriber access lineservice provider to handle the emergency call.

In one embodiment, the phone 517 recognizes the emergency call androutes the emergency call to a phone system from the subscriber accessline service provider. In another embodiment, the phone 517 is connectedto the subscriber phone equipment 510. The subscriber phone equipment510 recognizes the emergency call and routes the emergency call to aphone system from the subscriber access line service provider.

In another embodiment, the subscriber access line module 530 recognizesthe emergency call and routes the emergency call to a phone system fromthe subscriber access line service provider.

Types of Phone Calls that Require Subscriber Location Information

The above description applies to emergency calls that require subscriberlocation information. However, there are many other scenarios in whichwould be helpful, advantageous or necessary to obtain the subscriberlocation of a telephone call. In one embodiment, phone system can usesubscriber access line identities to determine the location informationfor calls such as location specific directory services, marketinginformation for premium pay per use phone services and toll-free servicecalls.

Foregoing described embodiments of the invention are provided asillustrations and descriptions. They are not intended to limit theinvention to precise form described. In particular, it is contemplatedthat functional implementation of invention described herein may beimplemented equivalently in hardware, software, firmware, and/or otheravailable functional components or building blocks, and that networksmay be wired, wireless, or a combination of wired and wireless. Othervariations and embodiments are possible in light of above teachings, andit is thus intended that the scope of invention not be limited by thisDetailed Description, but rather by Claims following.

1. A method for obtaining a subscriber location for a call from a phone,wherein the phone is coupled to a subscriber access line module via asubscriber access line, wherein the subscriber access line module iscoupled to a phone system, comprising: (a) determining by the phonesystem a subscriber access line identity of the subscriber access line;(b) sending a query from the phone system to a subscriber location querysystem, wherein the query comprises the subscriber access line identity;and (c) receiving from the subscriber location query system thesubscriber location corresponding to the subscriber access lineidentity, wherein the subscriber location comprises a physical or linklayer property of the subscriber access line module to which thesubscriber access line is coupled; and (d) determining by a subscriberphone equipment if an emergency call can be made using the subscriberaccess line, wherein the subscriber phone equipment is coupled to thesubscriber access line module via the subscriber access line, comprisingthe steps of: (d1) sending a query by an emergency call test module ofthe subscriber phone equipment to the subscriber access line module oran emergency phone system; and (d2) receiving a response from thesubscriber access line module or the phone system to the emergency calltest module indicating whether or not the emergency call can be made. 2.The method of claim 1, wherein the determining (d) further comprises:(d3) setting an emergency call test indicator of the subscriber phoneequipment according to the response.
 3. A system, comprising: asubscriber access line having a subscriber access line identity; asubscriber access line module; a phone coupled to the subscriber accessline module via the subscriber access line; a subscriber location querysystem, comprising a subscriber location corresponding to the subscriberaccess line identity; a phone system coupled to the subscriber accessline module, wherein the phone system receives a call from the phone viathe subscriber access line, wherein the phone system determines thesubscriber access line identity, wherein the phone system sends a queryto the subscriber location query system, wherein the query comprises thesubscriber access line identity, and wherein the phone system receivesfrom the subscriber location query system the subscriber location,wherein the subscriber location comprises a physical or link layerproperty of the subscriber access line module to which the subscriberaccess line is coupled; and a subscriber phone equipment coupled to thesubscriber access line module via the subscriber access line, whereinthe subscriber phone equipment comprises an emergency call test module,wherein the emergency call test module sends a query to the subscriberaccess line module or an emergency phone system, and receives a responsefrom the subscriber access line module or the phone system to theemergency call test module indicating whether or not an emergency callcan be made.
 4. The system of claim 3, wherein the subscriber phoneequipment further comprises an emergency call test indicator, whereinthe emergency call test indicator is set according to the response.